This section has been prepared by the URC judges and staff. The comments provided here are intended to be used as systems engineering lessons, and are not intended to replace, alter, clarify or modify the official Requirements & Guidelines or Q&A in any way. There is no template for building and operating a winning rover, but the points below have been prepared with careful consideration.
Proper design and testing of communications between the rover and base station is the key difference between being a top competitor and just sitting there.
Nothing is more heartbreaking - or common - in the URC than for a team to work hard all year, pass all the reviews, travel from far away, and then have their rover just sit at the starting line at the actual URC competition, motionless, because of problems with their communication system. Unfortunately, this happens all too often. A large number of all teams have severe trouble with their communication system (coms). Communication failures are far and away the most common problem that stops a team from being a top contender. The judges have observed that the top teams always have solid, reliable coms, and the teams with poor coms never do well. It doesn't matter how good your rover design is, or how hard you worked all year long, if you don't have reliable coms, you will not be a top contender. As a result, teams are strongly advised to put a lot of time and effort into ensuring that their com links are reliable.
Design your com system for both near and far operation.
Remember that most URC activities are very close to the control station, but that this may be over a wide angle - the rover will not always be 'in front' of your antenna. Teams need to make sure that they can support activity over a wide angle close by the antenna. Portions of some of the tasks are farther away or behind terrain. Teams need to be able to cover both close and far operation.
Design your com system for controlling from inside a metal building.
The terrain task uses the bottom floor of the “Hab” as a control station. This is a metal structure and radio signals, including Wi-Fi, will NOT go through the walls. Teams MUST mount their antenna outside of the hab, and bring a 25-meter long antenna cable to connect to their antenna from inside the Hab. If you don't bring a long enough cable, your coms will not work.
Design and test of your coms as a central part of your rover development.
Don't skip your com links, or rush it at the end. You should be designing and testing your com links well in advance. Test them over realistic distances and geometries, similar to what you will find at the URC. If your team is new to the URC, look at past videos to get an idea of the scale and scope of the terrain. For teams that live in countries that do not use the same radio frequencies as the US, test and train with the appropriate frequencies in your country, and be prepared for a simple switch upon arrival in the US, and then test the final design again. We also recommend that teams test their com links after they arrive at Hanksville before the competition. Test, test, test!
REPAIR, RELIABILITY, AND LOGISTICS
Design the overall system for ease of repair
It is an old saying in the military that amateurs will talk of strategy while professionals think of logistics, because that is what really determines who wins and who falls behind. Similarly, in URC logistics for transporting and operating the rover at the various challenge sites and the ease of repair during and between challenges need to be considered along with task capability and speed. Consideration should be given in the rover design, and in preparatory testing and training, for the ability to make rapid repairs. Parts and components can break and repairs will need to be made. Design features may need sudden modification. Software may need updating. Workarounds may need to be improvised.
Securing replacement parts in Utah may be a lot more difficult than at home. The URC site is several miles off-road from Hanksville, which is a small, rural town with limited resources. The nearest city where electronic and hobby parts can be found is Grand Junction, which is about a six-hour round trip. Cell phone service is not available at the URC site, so in case of an emergency part run, communication with the home team is not possible. You are not as isolated as actually being on Mars, but it is close!
Bottom line, it is best to make sure you have all the tools, supplies, and critical spare parts you may need. It is better to bring too much than to be short a critical part or tool. Also, before sending a team member on an all-day trip to Grand Junction for a part or tool, ask around with the other teams. URC takes great pride in the sportsmanship shown by competing teams.
Take a balanced approach to capability and reliability
It may be a winning strategy to adopt an ambitious rover design capable of performing all of every task in the competition. But the more complex a system is the less reliable it will be and, chances are, the more time it will take to design and build, leaving less time for testing and training. URC is a very tough competition, in which few (if any) rovers are able to complete every part of the competition tasks. Teams can strategize by deciding if they want to pursue a design that is more capable but more complex in order to increase their ability to complete an entire task, or decide to use a simpler but potentially more reliable design that may be more likely to accomplish at least a portion of a task.
Think carefully about the design features that are truly important
Many capabilities are good. But some are more important than others. For example, none of the tasks at URC would be particularly difficult to finish within the allotted time period if they were performed by an ordinary human at a walking pace: the rovers do not need superhuman capabilities. Think carefully about the specific actions that will be needed to perform each task, turn that into relevant performance characteristics, and then prioritize them over characteristics that are not as vital.
View the rover, communications, control, and operations as a single system
Remember that the competition is not just about the rover. Think carefully through all aspects of operation: the rover, logistical support, communication, and operation, and how that will be done in a remote, outdoor location
How will you have situational awareness? The ability to visualize one's surroundings with the view from an onboard camera is not as good as the human eye. The team should consider how to ensure adequate situational awareness to detect targets and obstacles, navigate, judge terrain, and hazards, especially in the new terrain traversing task.
How will you operate the rover? Navigation, route determination, and hazard avoidance merely gets you to where you want to go. How will you observe the activity you are performing? Will you have the dexterity and precision needed as well as the strength and the speed? Which characteristics are more important?
DESIGN, TESTING, AND TRAINING
Design for the three Rs: Reliability, Ruggedness, and Robustness
The University Rover Challenge (URC) takes place in a very harsh environment. The area is isolated, suffers from extreme temperatures, dust, high winds, and rugged, unpredictable terrain, varying from piles of rocks to powdery hillsides.
Rovers undergo a lot of shaking and vibration in their journey to the test site in the back of cars or rental vans, or in shipping crates, including the drive on the rough, unpaved roads from Hanksville to the URC site. Wiring and coms break and come loose. Just as in real Mars missions, where the vibration and shock of travel to which the rovers are subject is a major design consideration, the URC teams should make sure that their com systems can withstand a half hour of continuous shaking in their vehicle. Past URC teams have set up and had their rover work perfectly in the motel parking lot in Hanksville and then not work at all at the URC because of a loose wire or connector. Make sure antennas, connectors, and wires can withstand a rough ride—and then plan to test again when you arrive at the challenge site.
But of course the real rough ride begins during the challenges themselves. Rovers have been driven unintentionally into gulleys, and even flipped over. The best designs are of no use if the rover breaks down in the field. Think carefully about how a rover design will stand up in the field, not just operate in the lab (and that will bring you back to planning for repair.) And don’t forget to secure and ship your rover, including internal parts, so that it is not damaged in the shipping process to Utah.
Keep the design simple
It is an axiom of engineering that the simpler a design is, the more likely it will work. Conversely, the more complex a design the more it will need to be tested to ensure reliable operation. Unfortunately, more complex designs also require more time to design and build, leaving less time for testing and practice. Freezing the insertion of non-essential improvements to allow design stability during the later phases of testing is a common industry practice, especially with software. This does not mean avoiding novel or innovative designs or concepts, but rather weighing carefully the difficulty of developing complex features before deciding on adopting them.
Build it early, and test, test, test
It is a good idea to conduct testing continuously during each stage of the design and build process, especially if a rover involves new or unusual concepts. Any design feature that has not been tested in the lab cannot be counted on to work in the field. The parking lot of a Hanskville motel the day before the competition is not the place or time to first test a feature. This goes for software as well. Test in as realistic an environment as possible. What worked in the lab can and has failed in the URC field environment.
And don't forget to train, train, train
Just as important as having a well-designed rover is having a well-trained team. The team should show up at the URC familiar with operating, maintaining, setting up, and repairing the equipment, and quickly fixing problems as they arise. Remember that the URC events are all time limited, so a well-practiced team will have an advantage over one that is unfamiliar with its equipment. Practice and training should, like testing, strive to be done under realistic, field-like conditions. This applies to support equipment such as radio communications, displays, and controls as well as the rover itself.